Aircraft, including airplanes and helicopters, generally include various types of movable control surfaces such as flaps, ailerons, flaperons, elevators, rudders, wing tips, spoilers, tabs, slats, air brakes, and/or sleeves. Such movable control surfaces may, in certain instances, become nonresponsive. For example, hydraulic control circuits may become jammed, electrical circuits may be disconnected or severed, mechanical joints and/or connections may become disconnected or stuck, movable control surfaces may be iced over or otherwise damaged due to other environmental damage, and/or other additional failures may cause movable control surfaces to become non-responsive.
A hard-over is an example of a non-responsive state for a movable control surface. In a hard-over, a movable control surface may be permanently stuck in a certain position. The position may be, in the example of an aileron or flap, fully up or down, or some angle in-between. Such a non-responsive movable control surface may render the aircraft, more difficult to control and may also increase drag.